Methods for preparing a nanotube membrane for use in a pellicle membrane using dry printing are disclosed. Nanotube fibers are produced in a reaction vessel and dry sprayed onto a filter to form the nanotube membrane. The thickness of the nanotube membrane can be controlled by moving the reaction vessel and the filter relative to each other, or by further processing to reduce the thickness of the layer deposited onto the filter. This method reduces the number of process steps, reducing overall production time, and can also be used to produce larger membranes. The pellicle membrane can be formed with multiple layers and has a combination of high transmittance, low deflection, and small pore size. A conformal coating may applied to an outer surface of the pellicle membrane to protect the pellicle membrane from damage that can occur due to heat and hydrogen plasma created during EUV exposure.

A pellicle configured to protecting a photomask from external contaminants may include a metal catalyst layer and a pellicle membrane including a 2D material on the metal catalyst layer, wherein the metal catalyst layer supports edge regions of the pellicle membrane and does not support a central region of the pellicle membrane. The metal catalyst layer may be on a substrate, such that the substrate and the metal catalyst layer collectively support the edge region of the pellicle membrane and do not support the central region of the pellicle membrane. The pellicle may be formed based on growing the 2D material on the metal catalyst layer and etching an inner region of the metal catalyst layer that supports the central region of the formed pellicle membrane.

A pellicle configured to protecting a photomask from external contaminants may include a metal catalyst layer and a pellicle membrane including a 2D material on the metal catalyst layer, wherein the metal catalyst layer supports edge regions of the pellicle membrane and does not support a central region of the pellicle membrane. The metal catalyst layer may be on a substrate, such that the substrate and the metal catalyst layer collectively support the edge region of the pellicle membrane and do not support the central region of the pellicle membrane. The pellicle may be formed based on growing the 2D material on the metal catalyst layer and etching an inner region of the metal catalyst layer that supports the central region of the formed pellicle membrane.

A reflectivity and transmittance measuring device includes: an EUV light source for outputting EUV light with a wavelength ranging from 5 nm to 15 nm; a multilayer reflection zone plate having an EUV reflection multilayer film, which is a planar substrate, and a zone plate pattern; and an EUV lighting unit for creating EUV illumination light by obtaining 1.sup.st diffraction light reflected after radiating EUV light output from the EUV light source to the multilayer reflection zone plate.

A method of testing a photomask assembly includes placing the photomask assembly into a chamber, wherein the photomask assembly includes a pellicle attached to a first side of a photomask. The method further includes exposing the photomask assembly to a radiation source having a wavelength ranging from about 160 nm to 180 nm in the chamber to accelerate haze development, wherein the exposing of the photomask assembly includes illuminating an entirety of an area of the photomask covered by the pellicle throughout an entire illumination time and illuminating a frame adhesive attaching the pellicle to the photomask. The method further includes detecting haze of the photomask following exposing the photomask assembly to the radiation source. The method further includes predicting performance of the photomask assembly during a manufacturing process based on the detected haze of the photomask following exposing the photomask assembly to the radiation source.

A method of testing a photomask assembly includes placing the photomask assembly into a chamber, wherein the photomask assembly includes a pellicle attached to a first side of a photomask. The method further includes exposing the photomask assembly to a radiation source having a wavelength ranging from about 160 nm to 180 nm in the chamber to accelerate haze development, wherein the exposing of the photomask assembly includes illuminating an entirety of an area of the photomask covered by the pellicle throughout an entire illumination time and illuminating a frame adhesive attaching the pellicle to the photomask. The method further includes detecting haze of the photomask following exposing the photomask assembly to the radiation source. The method further includes predicting performance of the photomask assembly during a manufacturing process based on the detected haze of the photomask following exposing the photomask assembly to the radiation source.

A method for manufacturing a membrane assembly for EUV lithography, the method including: providing a stack having a planar substrate and at least one membrane layer, wherein the planar substrate includes an inner region and a border region around the inner region; and selectively removing the inner region of the planar substrate. The membrane assembly includes: a membrane formed from the at least one membrane layer; and a border holding the membrane, the border formed from the border region of the planar substrate. The stack is provided with a mechanical protection material configured to mechanically protect the border region during the selectively removing the inner region of the planar substrate.

A method for manufacturing a membrane assembly for EUV lithography, the method including: providing a stack having a planar substrate and at least one membrane layer, wherein the planar substrate includes an inner region and a border region around the inner region; and selectively removing the inner region of the planar substrate. The membrane assembly includes: a membrane formed from the at least one membrane layer; and a border holding the membrane, the border formed from the border region of the planar substrate. The stack is provided with a mechanical protection material configured to mechanically protect the border region during the selectively removing the inner region of the planar substrate.

Provided is an EUV transmissive membrane including a main layer composed of metallic beryllium and a protective layer composed of beryllium nitride that covers at least one side of the main layer.

A technique that enables production of pellicle membranes that are better resistant to breakage when subjected to force exerted thereon in the thickness direction thereof and that have high transmittance to light. A pellicle membrane of the present invention includes a plurality of laminated layers, where at least one of the layers is provided with at least one hole having a width or diameter of 10 nm to 500 nm.